Children of Latino-origin immigrants are the fastest growing sector of the US child population (Passel, 2011). Thus, it is important to examine how experiences in a country that is not the family's country of origin impinges on youth development. The proposed study seeks to examine how parent-youth acculturation differences (AD) among Latino immigrant families are directly and indirectly linked to youth emotional, behavioral, and cognitive functioning. Research examining the AD-youth outcomes relationship has rendered mixed findings (Telzer, 2010). Some work indicates a problematic association between AD on youth socio-emotional (Schofield, Parke, Kim, Coltrane, 2008), substance use (Marsiglia, Nagoshi, Parsai, Booth, & Castro, 2014), and behavioral (Szapocznik, Santisteban, Kurtines, Ferez-Vidal & Hervis, 1984) outcomes, while other work does not. Several methodological, conceptual, and measurement limitations have been noted in the current body of work. To reconcile these inconsistencies this study seeks to examine longitudinally: (1) how AD affects family processes that are central to youth development and are salient for immigrant families; (2) how AD affects youth emotional, behavioral, and cognitive functioning; and (3) how AD indirectly affects youth development through its effects on family processes. A sample of 450 Latino immigrant families will be recruited from high schools in the Central California area. Data will be collected every year for three years from these families on: parent and youth dimensions of acculturation (i.e., cultural values, identity, and language use); family processes that are important for youth development in general (i.e., parental monitoring, communication, and cohesion) and those that are salient among immigrant families (i.e., language brokering and parentification); and youth socio-emotional well-being, risk behaviors, academic achievement, and self-regulation. This study is positioned to make several important contributions to this area of research by: using a multidimensional approach in the measurement of acculturation; examining the longitudinal ramifications of AD on youth development; utilizing a statistically novel approach (latent- difference score analyses) to calculate the AD; identifying specific family processes that serve as mechanisms of influence in the AD-youth outcomes relationship; and informing future prevention efforts geared towards improving the well-being and reducing health disparities among Latino immigrant youth.